Update Antarctica guess tests for 2026

The last clock change for these zones was 2023, which now falls outside
the range of dates checked for guesses.

Author: gilmoreorless

tests/zones/antarctica/casey.js

@@ -4,9 +4,9 @@ var helpers = require("../../helpers/helpers");
 
 exports["Antarctica/Casey"] = {
 
-	"guess:by:offset" : helpers.makeTestGuess("Antarctica/Casey", { offset: true }),
+	"guess:by:offset" : helpers.makeTestGuess("Asia/Manila", { offset: true }),
 
-	"guess:by:abbr" : helpers.makeTestGuess("Antarctica/Casey", { abbr: true }),
+	"guess:by:abbr" : helpers.makeTestGuess("Asia/Manila", { abbr: true }),
 
 	"1968" : helpers.makeTestYear("Antarctica/Casey", [
 		["1968-12-31T23:59:59+00:00", "23:59:59", "-00", 0]
@@ -80,4 +80,4 @@ exports["Antarctica/Casey"] = {
 		["2023-03-08T15:59:59+00:00", "02:59:59", "+11", -660],
 		["2023-03-08T16:00:00+00:00", "00:00:00", "+08", -480]
 	])
-};
+};

tests/zones/antarctica/vostok.js

@@ -4,9 +4,9 @@ var helpers = require("../../helpers/helpers");
 
 exports["Antarctica/Vostok"] = {
 
-	"guess:by:offset" : helpers.makeTestGuess("Antarctica/Vostok", { offset: true }),
+	"guess:by:offset" : helpers.makeTestGuess("Asia/Karachi", { offset: true }),
 
-	"guess:by:abbr" : helpers.makeTestGuess("Antarctica/Vostok", { abbr: true }),
+	"guess:by:abbr" : helpers.makeTestGuess("Asia/Karachi", { abbr: true }),
 
 	"1957" : helpers.makeTestYear("Antarctica/Vostok", [
 		["1957-12-15T23:59:59+00:00", "23:59:59", "-00", 0],
@@ -24,4 +24,4 @@ exports["Antarctica/Vostok"] = {
 		["2023-12-17T18:59:59+00:00", "01:59:59", "+07", -420],
 		["2023-12-17T19:00:00+00:00", "00:00:00", "+05", -300]
 	])
-};
+};